The present invention relates to a card singularization gate for an identification card printer that provides non-abrasive contact with a surface of the lead card being fed while preventing multiple card feeds.
Identification card printers are generally adapted to print images onto surfaces of cards using a print mechanism. A supply of the cards (card stack) is typically stored in a hopper adjacent a card feeder. The card feeder is configured to feed a lead card of the card stack to a card transport mechanism, which presents the lead card to the print mechanism for printing. The print mechanism can be thermal or ink jet based. Thermal based print mechanisms include a thermal printhead that is adapted to heat a thermal print ribbon to cause dye to transfer from the ribbon to the surface of the card. Ink jet based print mechanisms include an ink jet printhead that receives a supply of ink that is applied to a special ink-receiving surface of the card. The ink-receiving surface, such as one formed of Teslin®, is generally delicate and can be damaged by abrasive contact resulting in poor ink reception and reduced printing quality.
One common problem that is encountered by identification card printers are misfeeds that occur when cards stick together during card feed operations. Such card misfeeds typically jam the card transport mechanism and render the printer inoperable to a user of the system until the jammed cards are removed. Such card misfeeds result in card waste, and reduce printing efficiency. To reduce the likelihood of card misfeeds, identification card printers are typically equipped with a card singularization gate between the card feeder and the card transport mechanism.
Conventional card singularization gates include a rigid plate that is positioned relative to a card feed plane to provide an outlet opening through which the lead card can pass while blocking any cards stacked thereon. However, the positioning of the plate is critical. For example, if the outlet opening is too large, double feeds of thin cards can occur. Similarly, if the outlet opening is too small, non-feeds of thick cards can occur. Card misfeeds can still occur even when the outlet opening is set slightly larger than the thickness of the lead card when, for example, the lead card is warped. As a result, frequent adjustment to the position of the plate relative to the card feed plane is often required.
These problems associated with card singularization gates that utilize rigid plates can be remedied by substituting the rigid plate with a flexible blade that is positioned such that the height of the outlet opening between a bottom edge of the flexible blade and the card feed plane is slightly less than a thickness of the lead card. During card feed operations, the flexible blade flexes in response to the lead card to allow the lead card to pass to the card transport mechanism while cards stacked upon the lead card are blocked by the flexible blade. This flexing of the blade allows the card singularization gate to accommodate cards of varying thickness as well as warped cards without adjustment.
Unfortunately, both the flexible blade and the rigid plate type card singularization gates can engage the lead card in an abrasive manner. Such abrasive contact can damage the delicate ink-receiving surface of the cards used in ink jet based identification card printers.
Accordingly, there exists a need for a card singularization gate for use in an identification card printer that reduces the likelihood of card misfeeds while providing non-abrasive contact with a surface of a lead card being fed on which an image is to be printed.